Environmentalists fear a rubbish tip near the Dryandra Woodland will harm the local numbats.

Supplied: Robert McLean

The Greens say a WA Government department is ignoring its own guidelines over a proposed rubbish tip near Dryandra Woodland, south-east of Perth, which could attract feral cats putting local numbats at risk.

They have accused the WA Department of Environment Regulation (DER) of not doing enough to ensure numbats were not affected by the dump planned for the Cuballing Shire.

"The Department of Environment Regulation, which has been advising this group of councils about the tip site, has failed to adequately warn them that it shouldn't be located so close to vulnerable population of native animals like the numbat and the woylie," MLC Lynn MacLaren said.

"Our research has shown that these councils have gone into it with the advice of DER and DER should've said it's too close to these areas."

It was estimated the nearby Dryandra Woodland is host to only about 50 numbats and environmentalists fear that an increase in feral cats could mean the end of the wild population.

Environmentalists say feral cats range over a large area, and there are other reserves within ten kilometres which need to be considered anyway.

Lynn MacLaren said the department's own guidelines warn against landfills, and environmental assessments were required.

"The guidelines are clear, landfills do create habitat for scavengers and predatory species, we know that they are a risk to the numbat population, the woylie population," she said.

The six councils behind the proposal, known as the Wagin Group, say they do not want numbats or other endangered species to be affected.

Smaller tips could close say councils

The group made the case that the large tip would allow smaller sites to be closed and there would be a positive environmental impact over time.

Its planning application submitted to the EPA said the councils' current landfill sites all had issues with "environmentally sensitive locations, future potential town planning issues or in some cases.. nearing capacity".

The EPA has decided not to assess the proposal, saying the Department of Environment Regulation could decide on potential impacts.

The EPA said it considered the "small geographic footprint" of the proposed tip, which would be on previously cleared land, and the distance from the Dryandra Woodland central block conservation reserves (approximately 10 to 12 kilometres).

The appeals convenor has taken submissions on the EPA's decision.

In a statement, the DER said it was yet to receive applications for a works approval or clearing permit.

The department said any new landfill would still require a works approval, and a licence or registration to authorise operations.

The federal Department of the Environment has also taken an interest, but to a limited extent.

In a statement, the federal department has said it was alerted to the proposal in early May 2015 by members of the public concerned about potential impacts on the vulnerable numbat.

On May 19, the department wrote to Cuballing Shire Council's chief executive officer to remind the council of its obligation to consider potential impacts from the proposal.